Consumer Cellular Apple Cell Phone Upgrade Reviews

So I called consumer cellular to ask to upgrade to a iPhone 6S from my iPhone 5S. Well they said no. That I have to finish paying off. Well I'm paying 650 dollars for this iPhone 5S. It only cost like 400 dollars or cheaper. They won't let me cancel and give them the phone back. Im getting scammed from them since im paying the same price as i can for Iphone 6s. Not to mention that it is a out dated phone. So i wanted to return the f*cking phone...